Balloon cap and method of its manufacture



y 8, 1952 w. F. HUCH ET AL 2,602,609

BALLOON CAP AND METHOD OF ITS MANUFACTURE Filed May 9, 1950 INVENTORS WlLLIAM F. HUCH RAYMOND l: HAKOMAKI BY C A TTORNE Y Patented July 8, 1952 BALLOON CAR AND METHOD or ITS MANUFACTURE 1 William F.-Huch, St. Paul; and Raymond I.

Hakomaki, Minneapolis, Minn.,,assignors to General Mills, Inc., a corporation ofDelaware Application Mayfl, 1950, Serial No. 1604971 The'present invention relates to balloons and 'more particularly to an imp'rovedmethod of capping balloons made of thermoplastic sheet material.

' Balloons are known in which the balloon body consists of a plurality of gores orsections of thermoplastic sheet material, these sections being seamed to each other attheir adjacent edges to form a gastight bag. It has been customary in the prior art, in order to avoid seaming difiiculties at the apex of the balloon,to make the end of each gore of definite width rather than having it taper to a sharp point. Thus the balloon body which is formed by joining the sides of adjacent ,gores will have top and bottom openings, at least one of which must then be capped in some manner. v

It is one obj ectof the present invention toprovide a novel balloonl cap wh ch can be readily manufactured without the problem of intersect ing se'ams at theapex of theballoon'. v i

'j A further object is the provision of a balloon cap in which an inte ral tubular 'extensionfis provided at theballoon apex, this extension being closed and sealedjand then covered by a proteceica m 1 l" .71

Still another objecti's the provision of ainovel balloon'gore construction for use in the provision ,oi'an improved balloon cap, '5 i H f A still further object is theprovisionfoi proved method for the "manufacture" of such cappedballoons. I v

Otherobjects and advantages will be apparent from the following specificationin. whichjafpreferred embodiment of theinvention isfdescribed.

In the drawings f orming agp art 'of this1 application and in which likere'ference. characters indiqa ef i epa si fl Figural is t a side balloon which canbe manufactured. according to the presentinvention.

Fig, 2 is a plan views; a novel ggoiieconstruction foru'se in such a ballo'onj.

Fig53 is a plan viewof a section construction table'or patt rn suitableforuse in production ofthe gore; of 'Fig. 2 and in 'the;as

final closingand capping.

ew similar;

Fig. 6 a is a similar perspective View showmgithe sealingof the balloon apex; v i

Fig. 7 is'a'top plan view of the apex ofthe elevation of one ja cent 'gores; bouldhave theirj edges' seamed to each other without'h'aving the seams'actually'iniof a balloon with respect to ,the center line 32, just I 10 Claims. (01.24%31).

balloon after it has been sealed, capped, and tape'dflan'd Fig. 8is an enlarged sectional view on' the line 8--8 of Fig. '7 showing details of the capping arrangement.

As shown in Fig. 1, the present invention has been described in connection with a balloon 2 ll having a spherical upper POItiQIliZZ and a conical or tapering lower section 24.; The bal1oon body consists of a plurality of vertically extending gores '26 which are seamed to each other at their adjacent edges in order to form a gasproof containen; This balloon body is provided with: a t p or cap 68 overlapping the upper ends of. the individualgores. j a

A plan view of one of the individual gores 26 is shown in Fig. [2, "Preferably a gore shapeis utilized which is symmetrica1 with respect to a longitudinal center line indicated. at." 32. 'Thus the gore has longitudinal edges 28 'and3ll, respectively, whichtaper in both directions toward the center line from an intermediate point of maximum width. [Edges 2s and so orthejgore substantially approach the center line at .a point 34 corresponding to the apex 0f the desired balloon, and also at a point 36, which corresponds to the lower end of the balloon'envelope.

. According to one prior art'rinethod; theiuppe'r or apex end of .thegore 26'would terminate atjth'e point 3.4 infan .end of definite width so thatfadtion .tech'niques to cap thecircular openingatthe apex ofsuch a balloon byjmeans ofa w'eldedor heat sealed seampefff orts havebeen made to provide a capping technique [which would .offejrlno manufacturing problem and which would result in a gastight envelope at this point;

7 According tothe presentinvention the upper end of each gore 2 6,is1provided wi-tha'dongitudl nal extension! "projecting beyond .the". point 34 which would normally be th e. upper nd-traps; of the gore;v 'Ihfi'sfext ension. 38 is symmetrical 'dividual gore edges 28 an.d 30 ar v v .Av gore of the, specificshape .s n, Fig. 2,. With'thecentral or axial extension 3Bat itsapex end," canfbe "advantageously manufacturedbn a pattern or balloon gore table. ofthe in Fig. 3. This table 4013 formed in sllb s fililtially bylthe reference 50.

the shape of one-half of the gore pattern. Thus table 40 has one straight edge 42 corresponding to the center line 32 of the desired gore.

The other edge 44 of the table 40 is shaped to correspond to the outer edge 28 or 30 of the gore 26-. Thus this outer edge 44 tapers in both directions toward the straight edge 42 from an intermediate point offmaximum table width. At what corresponds to the lower end of the' gore, the edge 44 substantially meets the straight table edge 42 as shown at 46. The width of the table atpoint 46 is just large enough to secure a bottom opening 1 At the apex or upper end of the-balloontable 40, the edge 44 approaches almost to the line of the straight edge 42 at point 48 corresponding to the apex of the balloon. However, instead of intersecting the edge 42 along a line indicated by the dotted portion 48, as would be the. case in the absence of the present invention, this particular table is. formed with a projection or extension at the apex end so that the curved: or contoured edge 44 includes an apex portion 52:.ex-

tending parallel tothe axis of .the straight edge '42 and spaced slightly away from said axis. In order to strengthen the balloon table at this point, a portion corresponding to the extension may be widened as shown at 54 to provide the necessary rigidity. The extension as a whole is indicated In operation, the table shownin 3 is used for the production of balloons with tubular thermoplastic material according to one or more of the methods shown in the copending applications of Stinger et al., Serial No; 160,973, filed May 9,

1950, for M-ethodand Apparatusifor. Manufacturing Balloons From Tubular Material, and Huch ,et val., .Serial No."160,97.2, filed May 9, 1950, for Balloon Manufacturing Method and Equipment,

both of which are assigned to the owner of the with the straight edge 42 of the table to con-v stitute the center line of the resulting gore. A strip'can then be trimmed along a line corre sponding to'thetable edge 44 and extension 52 toprov ide a'gore section which, ifunfoldjed, would 1 avethe'complete shape shown in Fig. 2. p v

In the construction of a balloon with such goresgjthe adjacentedges 28 and 300i the .respective gores are seamed to each other to provide 'a' strong and substantially gasproof balloon body, The seaming operationmay be carried on with different types of equipment and'with variousfinethods, but is ordinarily practiced while the material is laid out on the balloontable 40, according to one of themethods of the abovementioned patent applications. g

Fig.:' 4 shows in partial perspective the apex or 'npperflportionof a balloon bodymade. with'the gores of Fig. 2; In the making of such 'a balloon, the edges of adjacent gores are seamed to each other at .3'1, and this seaming operation is carrjied'oirt simultaneously between the edges of the extensions 38 at the 'apexof eachgore. Thus seams 31" are provided between theindiv'idual gores. ,fijlld these seams have .continuations or extensions indicated. at 39 between the edge'sof the respective gor'e projections 38; v

Thus the seams}? unite the gores to form the balloonbody, while the seams 39 unite the xtensions 38 of the'gores'to form anintegral tubu l ar-lei; ion ififiwhichprojects from the apex essinclude the-formation of a'plurali ty'of gores corresponding to the particular type of balloon desired, each of said gores being provided with an integral extension at one end. These extensions are sealed to each other in the same mannerras'thesides of the adjacent gores in order to form simultaneously a balloon body and an inh tegral tubular extension at one end thereof, pref- 15' erably the apex.

The next step .in the process is illustrated at L Fig. 5. According to this step it is necessary to close off the tubular extension 56 in some manner. While various methods can be used for the formation of this closure, the preferred form of the invention involves the twisting of the tubularextension 56 .so as to reduce its diameter to substantially the thickness of the individual layers of material. This twisting operation takes place immediatelyadjacent the upper portion 22 of balloon 20, and the twisted portion is then .tied or secured. A suitable tie may be made by the use of. a nylon cord '58 knotted to itself at 60. to "hold the twisted tubular extension inits closed condition.

As shown in .Fig. 6,. it is then possible to seal off the tubular extension beyond the tied portion byvthe use of a flame 52 from a portable burner 64in order to form a bead or globuleof molten material at'66 which effectively seals oif the up per end of the tubular extension 56. "A heated wire or other'sealer can also be used.

.The resulting balloon body has the necessary resistance to diffusion at all points, including the tied. and sealed extension 56. In order to.cover and protect this tied and sealed extension, a circular cap 68 of thermoplastic sheet material is placed. over the apex ofthejballoonlas shown in Fig. 'I. The cap 68 is then held in place .by a series or load bearingtapes 1,0 which are passed acros'sthe cap 68 and the balloon body'iin such a manner .asto overlie the individual seams 31 between the edges of adjacent gores. These load bearing tapes 10 crossover each, other at the exact apex of theb'alloon above the tied and sealed extensionjfis and thus prevent any sub stantial strain from being placed on the balloon envelope or onthe sealedtube.

YThese tapes 10 can then be extended downwardly over the entire length of the seams 31 and connectedto a suitableload bearing: ring atv the lower end of the balloonbody in the manner described and claimed in the 'Winzen Patent "2,526,719 assigned tothe owner of the present integral: axialjjextensionjat,one end. The ad jacentfedg'es ofithese gores of thermoplastic. sheet material'are then joinedto eachother; for example by a snitable heat seaming method and apparatus, to provide a continuous balloon envelope. At the same time that the edges of adjacent gores are seamed to each other, the corresponding edges of the gore extensions are also joined. These joined extensions provide an integral tube at one end of the balloon. When this tube is located at the apex of the balloon, it is then tied and sealed to close said apex. The tied and sealed tubular extension is then capped and protected by a circular piece of similar thermoplastic material which is held firmly in place by load bearing tapes extending across both the cap and along the individual seams between the adjacent gores of the balloon envelope.

It will be understood that the thermoplastic sheet material which is utilized is relatively thin and that the apparent thickness of the tied tubular extension as shown in Figs. 5, 6, and 8 is of necessity exaggerated for clearness. The actual thickness of the material at this point is relatively small so that the tied and sealed tube rests beneath the cap 68 without substantial deformation of the balloon apex. The preferred materials for the construction of balloons according to the present invention are polyethylene sheet material for the gores themselves and cellulose acetate or nylon tapes coated with pressure sensitive adhesive, for the load bearing members Ill.

Balloons made of these materials and capped in the manner described possess excellent resistance to difiusion as well as the necessary strength and rigidity for load bearing flights to substantial altitudes.

Since minor variations and changes in the exact details of construction will be apparent to persons skilled in this field, it is intended that this invention shall cover all such changes and modifications as fall within the spirit and scope of the attached claims.

We claim as our invention:

1. A balloon comprising a plurality of vertically extending gores of thermoplastic sheet material having their adjacent edges seamed to each other to form a gas tight bag, each gore having a relatively narrow integral extension at its apex, and

the edges of adjacent extensions. also being.

seamed to each other by extensions of the seams between adjacent gores to form a projecting tube of small diameter at the apex of the balloon, and means forming a gas tight closure for the tube.

2. A balloon comprising a plurality of vertically extending gores of thermoplastic sheet material having their adjacent edges seamed to each other to form a gas tight bag, each gore having a relatively narrow integral extension at its apex, and the edges ofadjacent extensions also being seamed to each other by extensionsof the seams between adjacent gores to form a projecting tube of small diameter at the apex of the balloon, securing means closing the tube adjacent the balloon apex, and a protective cap overlyin the closed tube.

3. A balloon comprising a plurality of vertically extending gores of thermoplastic sheet material having their adjacent edges seamed to each other to form a gas tight bag, each gore having a relatively narrow integral extension at its apex,

and the edges of adjacent extensions also being seamed to each other by extensions of the seams curing means closing the tube adjacent the ballon apex, a protective cap overlying the closed tube, and a plurality of load bearing tapes overlying said protective cap and. extendin in superimposed relation along the seams between the gores.

j 4. A balloon according to claim 3 in which at least one loadv tape overlies each of the seams between adjacent gores and extends all the way from the apex of the balloon above said cap to the lower end of each gore seam. v

5. A balloon according to claim 3 in which the protective cap is free of attachment to theballoon in the areas between the tapes.

6. A balloon gore having spaced longitudinal edges symmetrically located with respect to a longitudinal center line and converging toward the center line at each end of the gore, the gore having an integral, relatively narrow extension projecting at one end of the gore along said center .line beyond the normal apex of the gore.

7. A balloon gore according to claim 6 in which the narrow extension has straight edges spaced symmetrically at each side of the center line.

8. A balloon gore according to claim '7 in which the straight edges of the narrow extension are joined to the longitudinal gore edges by smoothly curved portions.

9. A process for making and capping multiplegore balloons which comprises forming a plurality of identical gores of thermoplastic sheet material, each gore having longitudinal edges spaced from a common center line and converging toward the center line at each end of the gore, and each gore having a relatively narrow extension projecting axially from the end of the gore along the center line, successively seaming together the edges of adjacent gores and also seaming together the edges of adjacent extensions and thereby forming a hollow balloon body having an axial tubular extension at one end.

10. A process for making and capping multiple-gore balloons which comprises forming a plurality of identical gores of thermoplastic sheet material, each gore having longitudinal edges spaced from a common center line and converging toward the center line at each end of the gore, and each gore having a relatively narrow extension projecting axially from the end of the gore along the center line, successively seaming together the edges of adjacent gores and also seaming together the edges of adjacent extensions and thereby forming a hollow balloon body having an axial tubular extension at one end, closing the tubular extension and folding it down on the balloon body, positioning a protective cap above the closed and folded down extension, and tapping the protective cap to the balloon body.

. WILLIAM F. HUCH.

RAYMOND I. HAKOMAKI.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

